Fluid pressure actuated grippers are widely employed and typically take the form of a pneumatic or hydraulic differential motor whose cylinder is fixedly mounted to a transfer device. At the forward or rod end of the cylinder housing, a gripper jaw mounting structure is fixedly mounted on the cylinder to pivotally support a pair of opposed gripper jaws which are coupled to the piston rod of the motor by a linkage so arranged that upon movement of the piston in one direction, the jaws are pivoted to an open position, and upon movement of the piston in the opposite direction, the jaws are driven to a closed workpiece gripping position.
In typical operation, the gripper jaws will be closed upon a workpiece near the edge of the workpiece, and the gripper will be advanced to position the gripped workpiece in operative relationship with a work station. The gripper will then be opened to release the workpiece, and the transfer device will retract the gripper from the work station while the work operation is performed. At the conclusion of the work operation, the gripper will then advance back into the work station, and the jaws will again close upon the workpiece and carry it away from the work station. Opening and closing the gripper jaws thus takes place when the gripper is in its closest proximity to tooling at the work station.
Fluid pressure actuated grippers are generally designed for use with particular workpieces to be transferred and with specific work stations. For example, some workpieces and/or work stations may require wider or narrower gripper jaws, different types of gripper jaws, gripper jaws that open at different angles, different clearance requirements, etc.
The present disclosure is directed to gripper jaw tips and jaw tip assemblies for fluid pressure actuated grippers which allow for the gripping, sensing, and transferring of a variety of workpieces.
Accordingly, an illustrative embodiment of opposable gripper jaw tips is provided. The gripper jaw tips comprise first and second jaw tips. A base is provided integral with the first jaw tip, as well as a spherical concave gripping surface. The second jaw tip also has a base and has a spherical convex gripping surface. The spherical concave gripping surface of the second jaw tip being complimentarily shaped with the spherical convex gripping surface of the first jaw tip.
Other illustrative embodiments may include the first jaw tip and the spherical convex gripping surface of the second jaw tip, each having a radius of curvature of at least about 0.25 inches. The spherical concave gripping surface of the first jaw tip and the spherical convex gripping surface of the second jaw tip may alternatively each have a radius of curvature of about 0.80 inches. The first jaw tip and the second jaw tip may each further include a threaded stud for securing the jaw tips to gripper jaw members.
Another embodiment may provide a modular gripper assembly having a body, first and second opposable jaw members, and first and second jaw tips. The body includes a yoke structure defined at one end thereof by a pair of spaced-apart wall members, and an actuator at an opposite end. The first and second opposable jaw members, each have tip ends which are aligned with one another. In addition, at least one of the pair of opposable jaw members is pivotal. The first jaw tip is coupled to the tip end of the first opposable jaw member. This first jaw tip has a spherical concave gripping surface. The second jaw tip is also coupled to the tip end of the second opposable jaw member. This second jaw tip has a spherical convex gripping surface. The spherical concave gripping surface of this second jaw tip is complimentarily shaped with the spherical convex gripping surface of the first jaw tip.
Additional features and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of the preferred embodiment exemplifying the best mode of carrying out the invention as presently perceived.